(Welcome! I’ve moved this to projects so you can get individualized responses based on your own needs and preferences.)
SmartThings can do a lot of things very well, but unfortunately it’s fairly weak when it comes to handling colored lights in groups. With the official features, there isn’t even a way to create a color scene. Nor can it use the scenes created in the official Hue app, even though there is an official integration between SmartThings and Hue.
It can definitely do the “all lights off” and motion sensor options, but when it comes down to precise management of lighting scenes, it’s just not very good at that.
It does work well with Amazon Alexa. The Sonos integration is complicated. At one point customers were being advised not to add more than one Sonos device because having more than one could cause problems with the entire network. I don’t know if that’s still true. But in any case you can’t select playlists or other granular Control with the official features.
There are some community developed offerings which add a lot to the functionality. ActionTiles, which you mentioned, is very good and very popular. You will find much mention of it in the forums. (The original version was called SmartTiles.) there’s even an entire topic just about different hardware options to use with it. You might get some good ideas there regardless of what specific solution you end up going with.
Core is a community – created rules engine, lets you set up much more complex rules than the official features, such as your example of “and the lights are off” – – it’s pretty amazing. Complicated, but there are many community members who will be glad to help you set up specific rules (which core calls “Pistons”). It doesn’t manage existing Hue scenes, though, you basically have to re-create each one in core.
So…if “understands preset scenes” means “understands the preset scenes created through the Hue app,” then SmartThings is not a good match.
And if “works with Sonos” means “works with all the features available through the official Sonos app” then again, SmartThings is not a good match.
Interestingly, none of the devices you mentioned require use of one of the radios inside the SmartThings hub. They are all external integrations. For that reason, you might be able to get a lot of what you want just with a software solution such as IFTTT or stringify or yonomi even a combination of all three.
(Smartthings works with both IFTTT and Stringify but, as I mentioned, I’m not sure you need the SmartThings piece at all.) Yonomi would be another “master app” candidate, except I don’t think it works with Tado. Stringify doesn’t work with Tado directly, but IFTTT does, so I think you would have to add that in. Unfortunately, I originally thought stringify works with Sonos, but I had it confused with yonomi. So I’m not sure exactly how you’re going to be able to work the Sonos piece in.
So my suggestion for the moment would be to start with Stringify, and see how far you get.
You’ll also need the Tado IFTTT channel.
https://support.tado.com/hc/en-gb/articles/205806049-Which-IFTTT-Services-does-tado-offer-
And if you want to see what you can do with Sonos, you may need to look at yonomi as well. Yonomi does give you integration between Alexa and sonos, so depending on the exact use cases, that might be enough.
http://support.yonomi.co/knowledge_base/topics/using-alexa-and-sonos-together
It may be that that’s enough to meet all of your existing requirements. I’m not sure what SmartThings would add to the solution for you, since you don’t have a hardware requirement for it given the list you presented. And Stringify has better granular control of Hue lights and scenes.
You can always add SmartThings in later if you find you do you have a need for it, but with your particular situation, I would start with stringify. 